/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* 全局样式 */
body {
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* 头部样式 */
header {
    background-color: #2c3e50;
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 20px;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 20px;
}

nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

nav a:hover {
    color: #3498db;
}

/* 卡片样式 */
.card {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    padding: 20px;
    margin-bottom: 20px;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    background-color: #3498db;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    text-decoration: none;
    font-size: 16px;
    transition: background-color 0.3s;
}

.btn:hover {
    background-color: #2980b9;
}

/* 表单样式 */
.form-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

input,
select,
textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

/* 表格样式 */
table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

table th,
table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

table th {
    background-color: #f8f9fa;
    font-weight: 600;
}

/* 响应式设计 */
@media (max-width: 768px) {
    nav ul {
        flex-direction: column;
    }
    nav ul li {
        margin: 10px 0;
    }
}